I don’t know if this is the right place for it, but an idea I’ve had:
Charge a high tax penalty on home ownership if the home is fully functional and livable, but spends over a certain percentage of the year unoccupied by any person as their primary residence (and a steadily accumulating tax for any home that spends too many years in an unlivable state)
This might put pressure back on landlords to put their homes on market for reasonable prices, instead of inflating their rents based on MBA recommendations long past what people can pay simply to “keep the property value high”. It would severely devalue the idea of owning homes the same way you would own piles of gold, as long-term investments people are hesitant to actually use.